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Konjac glucomannan (KGM) is a viscous dietary fibre that can form a solid, low-energy gel when hydrated and is commonly consumed in a noodle form (KGM-gel). Increased meal viscosity from gel-forming fibres have been associated with prolonged satiety, but no studies to date have evaluated this effect with KGM-gel. Thus, our objective was to evaluate subsequent food intake and satiety of KGM-gel noodles when replacing a high-carbohydrate preload, in a dose–response manner. Utilising a randomised, controlled, cross-over design, sixteen healthy individuals (twelve females/four males; age: 26·0 (sd 11·8) years; BMI: 23·1 (sd 3·2) kg/m2) received 325 ml volume-matched preloads of three KGM-gel noodle substitution levels: (i) all pasta with no KGM-gel (1849 kJ (442 kcal), control), half pasta and half KGM-gel (1084 kJ (259 kcal), 50-KGM) or no pasta and all KGM-gel (322 kJ (77 kcal), 100-KGM). Satiety was assessed over 90 min followed by an ad libitum dessert. Compared with control, cumulative energy intake was 47 % (−1761 kJ (−421 kcal)) and 23 % (−841 kJ (−201 kcal)) lower for 100-KGM and 50-KGM, respectively (both P<0·001), but no differences in subsequent energy intake was observed. Ratings of hunger were 31 % higher (P=0·03) for 100-KGM when compared with control, and were 19 % lower (P=0·04) for fullness and 28 % higher (P=0·04) for prospective consumption when comparing 100-KGM to 50-KGM. Palatability was similar across all treatments. Replacement of a high-carbohydrate preload with low-energy KGM-gel noodles did not promote additional food intake despite large differences in energy. The energy deficit incurred from partial KGM-gel substitution may have relevance in weight loss regimens, and should be further evaluated beyond the healthy population.

Experiments on the National Ignition Facility show that multi-dimensional effects currently dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seeded by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of inertial confinement fusion implosions is the high convergence required to achieve high fusion gains. To tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. LANL has adopted three main approaches to develop a one-dimensional (1D) implosion platform where 1D means measured yield over the 1D clean calculation. A high adiabat, low convergence platform is being developed using beryllium capsules enabling larger case-to-capsule ratios to improve symmetry. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the implosion convergence can be controlled via the initial vapor pressure set by the target fielding temperature. The last method is double shell targets. For double shells, the smaller inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. However, double shell targets have a different set of trade-off versus advantages. Details for each of these approaches are described.

Oats are a rich source of β-glucan, a viscous, soluble fibre recognised for its cholesterol-lowering properties, and are associated with reduced risk of CVD. Our objective was to conduct a systematic review and meta-analysis of randomised-controlled trials (RCT) investigating the cholesterol-lowering potential of oat β-glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for the risk reduction of CVD. MEDLINE, Embase, CINAHL and Cochrane CENTRAL were searched. We included RCT of ≥3 weeks of follow-up, assessing the effect of diets enriched with oat β-glucan compared with controlled diets on LDL-cholesterol, non-HDL-cholesterol or apoB. Two independent reviewers extracted data and assessed study quality and risk of bias. Data were pooled using the generic inverse-variance method with random effects models and expressed as mean differences with 95 % CI. Heterogeneity was assessed by the Cochran’s Q statistic and quantified by the I2-statistic. In total, fifty-eight trials (n 3974) were included. A median dose of 3·5 g/d of oat β-glucan significantly lowered LDL-cholesterol (−0·19; 95 % CI −0·23, −0·14 mmol/l, P<0·00001), non-HDL-cholesterol (−0·20; 95 % CI −0·26, −0·15 mmol/l, P<0·00001) and apoB (−0·03; 95 % CI −0·05, −0·02 g/l, P<0·0001) compared with control interventions. There was evidence for considerable unexplained heterogeneity in the analysis of LDL-cholesterol (I2=79 %) and non-HDL-cholesterol (I2=99 %). Pooled analyses showed that oat β-glucan has a lowering effect on LDL-cholesterol, non-HDL-cholesterol and apoB. Inclusion of oat-containing foods may be a strategy for achieving targets in CVD reduction.

We describe an optical, spectroscopic survey of the nuclei of the 500 brightest galaxies in the northern sky. The primary goal is to search for low-luminosity active galactic nuclei (LLAGNs) in the centers of nearby galaxies. The results of this survey will have many astrophysical applications, including quantifying the faint end of the local AGN luminosity function and estimating the contribution of LLAGNs to the X-ray background. We summarize the statistical properties of the survey, describe our methods of analysis, and present some preliminary results based on ∼ 60% of the sample.

The inner few hundred parsecs of the Milky Way, the Central Molecular Zone (CMZ), is our closest laboratory for understanding star formation in the extreme environments (hot, dense, turbulent gas) that once dominated the universe. We present an update on the first large-area survey to expose the sites of star formation across the CMZ at high-resolution in submillimeter wavelengths: the CMZoom survey with the Submillimeter Array (SMA). We identify the locations of dense cores and search for signatures of embedded star formation. CMZoom is a three-year survey in its final year and is mapping out the highest column density regions of the CMZ in dust continuum and a variety of spectral lines around 1.3 mm. CMZoom combines SMA compact and subcompact configurations with single-dish data from BGPS and the APEX telescope, achieving an angular resolution of about 4″ (0.2 pc) and good image fidelity up to large spatial scales.

Between 1984 and 1990 we conducted a survey at Palomar Observatory (Filippenko and Sargent 1985) to quantify the luminosity function of nearby active galactic nuclei (AGNs). The Hale 5 m telescope was used to obtain high-quality, moderate-resolution optical spectra of a nearly statistically complete sample of about 500 bright (BT ≤ 12.5 mag), northern (δ > 0°) galaxies (see Ho et al. 1995 for details). The survey has now been completed, and the first scientific results are reported in a series of papers by Ho et al. (1997a, b, c).

We present new and archival Hubble Space Telescope (HST) images of circumnuclear star-forming rings in barred spiral galaxies. We find that nuclear rings in barred galaxies are composed of large numbers of super star clusters similar to those found recently in other types of starburst systems. In NGC 1097 and NGC 6951, the young clusters have absolute magnitudes of up to Mv = −14 or −15, depending on highly uncertain extinction corrections, and effective radii of 2–3 pc. The images (especially that of NGC 6951) also show intricate spiral dust lane structure interior to the rings.

Theoretical studies suggest that large-scale stellar bars can be highly effective in delivering gas to the central few hundred parsecs of a spiral galaxy, which may then initiate rapid star formation. Further instabilities may lead to additional inflow to physical scales relevant for active galactic nuclei. We test these predictions in light of recent observations. Compared to unbarred spirals, barred galaxies of type S0-Sbc have a higher probability of exhibiting nuclear star formation, as well as a higher formation rate of massive stars; neither effect is present in spirals of later morphological type. Bars, on the other hand, do not have an obvious influence on active nuclei. We discuss the implications of these findings for the fueling of central star formation and active nuclei.

During the early stage of an epidemic, timely and reliable estimation of the severity of infections are important for predicting the impact that the influenza viruses will have in the population. We obtained age-specific deaths and hospitalizations for patients with laboratory-confirmed H1N1pdm09 infections from June 2009 to December 2009 in Hong Kong. We retrospectively obtained the real-time estimates of the hospitalization fatality risk (HFR), using crude estimation or allowing for right-censoring for final status in some patients. Models accounting for right-censoring performed better than models without adjustments. The risk of deaths in hospitalized patients with confirmed H1N1pdm09 increased with age. Reliable estimates of the HFR could be obtained before the peak of the first wave of H1N1pdm09 in young and middle-aged adults but after the peak in the elderly. In the next influenza pandemic, timely estimation of the HFR will contribute to risk assessment and disease control.

A maskless method of employing polymer growth inhibitor layers is used to modulate the conflicting parameters of density and alignment of multi-junction nanowires via large-scale low temperature chemical route. This low temperature chemical route is shown to synthesize multi-junction nanostructures without compromising the crystal quality at the interfaces. The final morphology of an optimized multi-junctions nanowire arrays can be demonstrated on various substrates due to substrate independence and low temperature processing. Here, we also follow-up on device demonstrations whereby p-n junction are created by exposure of secondary nanowires to ammonia plasma, converting them to p-type characteristics and also the density modulated multi-junction nanowires were tuned to infiltrate nanoparticles to create a hybrid hierarchically-structured nanowire/nanoparticles solar cell. The fabrication of hierarchically-structured nanowire/nanoparticles composites presents an advantageous structure, one that allow nanoparticles to provide large surface areas for the dye adsorption, whilst the nanowires can enhance the light harvesting, electron transport rate, and also the mechanical properties of the films. This work can be of great scientific and commercial interest since the technique employed is of low temperature (< 90 °C) and economical for large-scale solution processing, much valued in today’s flexible display and photovoltaic industries. In addition, ZnO nanostructures for gas sensing will be presented.

Fluorescent dyes including Nile Red (NR), fluorescein, rhodamine and 4- (dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) derivatives were investigated to find an application for the organic light emitting device (OLED). Relationship between the molecular structure and optical property was calculated by ab initio (HF and DFT/6-31G*) and semiempirical (AM1/PM3 and INDO/S) calculation methods for the geometry optimization and for the information of electronic transition, respectively. The absorption maximum and the oscillator strength of molecules strongly depended on the molecular dipole moment, especially for the molecules having both strong electron donor and acceptor group. Since the calculated results were comparable with several experimental results, these semiempirical molecular orbital calculation methods could be used as a powerful prediction tool for optical properties of the luminescent molecules.

Ion beam mixing has been used to form layers of titanium disilicide on Si wafers. Doses of Ge+ up to 1×1016 ions/cm2 were implanted at 140 keV through 51 nm of sputtered Ti. The substrate was held at different temperatures; 150°C, 300°C and 400°C. In addition, some samples were processed without temperature control. Two rapid thermal annealing cycles were used, 800°C for 10 s and 650°C for 50 s in an N2 ambient to form stoichiometric TiSi2. As-implanted samples showed an increase in the number of mixed Ti and Si atoms with higher implant temperature and larger dose. In addition, a thin layer with a Ti/Si ratio of 1:1 as seen in some samples indicating possible TiSi phase formation. Lower implant temperatures, higher doses and higher anneal temperatures all produced greater TiSi2 thicknesses. Ion beam mixing yields thicker. silicide layers than those formed without mixing. The silicide interface smoothness was improved by ion beam mixing although some residual implant damage was observed after annealing. The implanted Ge+ accumulated below the silicide/Si interface and in the surface Ti oxide layer.

GaN thin films have been deposited on Si and sapphire substrates by metalorganic chemical vapor deposition (MOCVD) using diethylgalliumazide and ammonia. Films were grown in the temperature range of 500-750°C. Growth rates were monitored in situ using laser interferometry. The addition of ammonia enhanced the growth rate significantly. At high temperatures, gas-phase depletion of the precursor reduced the growth rate of GaN. Films grown on (0001)-oriented sapphire substrates at temperatures above 650°C were highly textured with smooth surface morphology. Optical and electrical properties of the films are discussed and compared to those of films grown using conventional Ga and N sources.

Molecular chlorine is scattered from a GaAs(100) surface and the reaction products detected by a mass spectrometer. A careful analysis of the velocity and angular distributions of the reaction products as well as the vibrational energy dependence of the daughter ion fragmentation pattern shows that the steady state reaction is stoichiometric in the removal of Ga and As until the incongruent evaporation rate exceeds the etch rate induced by the incident chlorine flux. The depletion of the nonreactive molecular chlorine signal is accounted for by the flux of chlorinated reaction products. The absolute etch rates as well as the incident chlorine flux are determined from the known evaporation rate of GaAs at the incongruent evaporation temperature. Modulated molecular beam scattering is used to establish some necessary reaction steps.

The interaction of SiO radicals from a SiCl4/O2 plasma with the surface of a depositing thin film is studied with the IRIS (Imaging of Radicals Interacting with Surfaces) technique, which combines spatially-resolved laser-induced fluorescence with molecular beam methods. In contrast to previous results for SiH, SiO appears not to react at the surface of the depositing film, but desorbs with a cosine spatial distribution for a wide range of substrate temperatures. No evidence is observed for specular scattering of the molecules.

Xerogel films of high porosity were fabricated using an ambient pressure technique. The same porosity can be obtained with different microstructures by varying the aging time of the films. The dielectric constant of these films as a function of porosity at 1 MHz follows correlations originally developed for bulk aerogels. Diffusion of copper is orders of magnitude faster in these xerogels than in the corresponding thermal oxide. An activation energy of 0.9 eV was estimated based on a convective diffusion model.